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LAFAYETTE HUNTOON, OF MILE'ORD, MASSACHUSETTS.

' Lene/rg Patent No. 63,638, dated April e, leer.

IMPROVEMENT IN STEAM ENGINES. i.

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TO ALL TO WHOM THESE PRESENTS SHALL COME:

Be it known that I, LAFAYETTE HUNTooN, oi' Milford, county of Worcester, and State of Massachusetts, have invented certain new and useful improvements in Steam Engines, and de hereby declare the following to be a full, clear, and exact description oi' the same, reference being had to the accompanying drawings, making part of this specification, and in which- Figure 1 is a top View or plan.

Figure 2, a side elevation; and

Figure 3, a vertical and transverse section through the middle of the cylinders.

Figure 4 is a longitudinal section of the steam chest and small cylinder with its steam ports.

Figure 5 is a longitudinal section of the large cylinder.

Figures 6 and 7 are sections ci' the steam chest with its valve andsteam ports, thcsainc to be hereinafter described.

Figure 8 is a top view of the two cylinders and steam chests, the top et the latter removed.

My present invention may be considered as an improvement on that for which Letters Patent of-the United States,"dnted the 15th day of May, 1866, were issued to me for certain improvements in steam engines, although in some respects the invention may be said to be an independent one, and applicable to all engines in which two cylinders are used, in which the exhaust steam from one cylinder is carried into and used expansivcly in the other or larger cylinder.

The object of the invention is to simplify the construction and lessen the cost of the engine, reduce the friction to a considerable extent, and give the engine a compact and symmetrical appearance.

The invention consists in the novel construction and arrangement of the valve chest, valve, and steam ports or passa-ges, whereby one steam chest and valve only for the-two cylinders becomes necessary in place of two as now generally employed. The invention further'consists inV several minor features to be hereinafter explained.

Byreferring to the drawings above mentioned as constituting part of this specification, it will bc seen that the bed of the engine is shown at A as supporting the two cylinders, of which C is the lesser and D the larger, the latter-being or" the same length as the former, but of double diameter, the two cylinders being placed side by side or cast in one piece of metal. E is the piston of the lesser` cylinder, shown in dotted lines in the diderent figures; Gr H being piston-rods. These piston-rods are connected to the two cranks I J of the drivingA shaft K byv connecting-rods L M, the said cranks I J being situated at right angles to each other. A ily-wheel, N, is applied to the driving-shaft K, which also carries an eccentric, which is encompassed by the strap P, of the eccentric-rod Q, which is joined to a vibrating-arm or lever, It, fixed to the outer end of a short horizontal rocken-shaft, S, which is dulyF supported by a standard erected upon thc bed of the engine, as shown in the drawings, or making part of one of the pistoirhead guides b Z1 I1. A connecting-rod or pitman, is connected with the vibrating-arm E, by a suitable sliding connection, (that exhibited in the drawings being a dovedailed recess, a, formed in the outer face of the arm, in which a dove-tailed stud, Z2, fromthe connecting-rod, slides,) the opposite end of this connecting-rod U beingjointed to the wrist of a crank or arm, V, applied to the outer extremity of' a rocher-shaft, W, supported in bearings, a a', made in opposite sides of the valve-chamber X of the steam chest Y, the said rocker-shaft haring a finger, Z,'the lower ond of which extends into a recess or notch, c', made in the upper surface of thc valve c, and serves to impart to the valve its proper movements. This valve has two steam recesses or chambers, d ci, formed 4in it to operate in connection nith the steam ports, in manner as hereinafter described. A regulator oi' ordinary construction, the n'elllnown Judson regulator for instance, is to lbc so combined with the engine that its operating stein shall be connected with the dovex tailed slide oi" thc connectinguod U before referred to. AS the regulator stem rises and falls Withthe accelc rating er diminished speed of thc engine, 'the stud b,- of the connectingrod U, is carried further away from or brought nearer to the axis of the vibrating-'arm E or its rocher-shaft S. It will be readily seen that this increases or diminishes lthe length of movement of the valve and regulates the amount of steam admitted to the cylinderJ The operation of the engine is as follows: We will suppose the piston E to be in one'. of its extreme positions at the end of the cylinder, as shown in fig. el of thc drawings. Atthis point thc piston moves very slowly. as its crank is just passing the dead-centre. '.lhe valve-eccentric, however, being applied to the driving-shaft at about right angles to the crank, moves the valve very quickly in the samedirection as the piston, until it opens the port e and allows the steam at a pressure of one hundred pounds to enter the cylinder through the port e in advance of the piston, and force the piston forward ono-half the length of its stroke, at which point the valve ceases its motion in this direction, at the position shown in iig. 6 of the drawings. As the piston advances the valve c is moved in an opposite direction owing te the position and action of its eccentric, and as the piston has travelled ve-eighths of its stroke, as shown in fig. T, thc valve has closed the port c and cnt oil' the entrance of steam to the cylinder at iiveeighths stroke, as it is termed, thus allowing the piston to be propelled the remaining distance by the expansive power of the steam, which reduces its pressure to about fifty orA sixty pounds. As the piston reaches the extreme end .of the cylinder it is again nearly stationary as at first starting, while thc valve moves quickly and allows the full pressure of steam to enter the cylinder, und against the piston through a port, c, situated at its opposite cud. As the piston moves back in the opposite direction the port c is opened, and allows theexhanst steam from the smaller cylinder' C (at a pressure oi' fifty or sixty pounds as before stated) to pass through it into the chamber cil of the valve e, from whence it passes into the larger cylinder D, thriough a passa-ge, f, also open at this point, and lcading'froin the cylinder C, as shown in iigs. 3 and 8 of the drawings, the exhaust steam performing its oilice in this larger cylinder I) in preciselythc same manner as the steam in an ordinary cylinder, and exhaustingand returning through this passagcf bnclc into the chamber el of thc valve, and thence through a main exhaust passage, y, which opens into the atmosphere in the usual manner, this main exhaust passage passing partially round both cylinders. The port e above referred to constitutes one of two ports or passages formed and situated precisely like the passages of, but at the opposite ends ofthe cylinder, the exhaust passage g being common to both. As their operation is the saine it will be understood, without more elaborate description, by engineers and`machinists,'to whom this specication is chiefly addressed.

The above description will also enable them orcthers to see that I make one steam chest and valve answer the purpose of two as heretofore employed, or as shown in the patent above referred to. The above description is based upon the supposition that the regulator before referred to is so adjusted as to give the valve its extreme 0r ,longest movement, the employment of the regulator, with the peculiar mechanism to which itis attached, enabling me to change this movement of the valve so as to cut olf the steam at any desirable point.

By referring to fig. 5 of the drawings, it will be seen that thc cylinder D is supplied with a valve u n, at each end, such valves communicating with its interior and opening into the atmosphere. These valves are ordinary check-vitlves, a section of' one of which is given in fig. 5, their purpose being as follows: If the engine has very little work to perform, and consequently needing little steam, and the regulator is so adjusted to the valveoperating mechanism as to cause the valve to admit little steam to the first cylinder, the exhaust, as it enters the larger cylinder, will not he suilicient to move its piston, or to till the vacuum which would bc created by the forward movement of the piston therein. The object of the valves is-to open as the piston reccdes from them, under these circumstances, and'allow thc atmospheric air to enter the cylinder and supply the place of the exhaust steam and break thc vacuum which would otherwise be created. If the pressure of thc exhaust is suflicient to exert any force upon the piston and counteract the tendency to vacuity, the valves will be closed by this pressure and prevent entrance 'to the cylinder from the atmosphere.

Having thus described my invention, and its mode of operation, what I claim, and desire to secure by Letters Patent, is as follows: v

1. I claim the combination, with the steam cylinders, of the steam chest and valve and ports for conducting the steam to and from the said cylinders, under the arrangement herein specified, so that but one valve and steam 'chest need he employed with the said cylinders as set forth.

2. I claim the arrangement of the herein-described mechanism for operating the valve, the saine consisting of the rocker-shaft S, vibrating recessed arm R, connecting-rod U, with its dove-tail stud b, and the rockershaft W, with its crank V and finger Z, the said mechanism being connected with the eccentric-rod Q, substantially as and for the purposes set forth.

' LAFAYETTE HUN'IOON.

Witnesses C. W. BALDWIN, Encounter( Gomis. 

